I'm a little late on this, but I'll recommend flushing the trans cooler in it now as well at a minimum. If you can find an OE style replacement for a reasonable cost I'd say opt for that. Just my $.02, but as stated, metal particles can still be in there and cause more issues on down the line, although it's a beater, $50 is still cheaper than missing a few hours or a day of work and paying for a tow.